Single line repeater



y 2 1932- v F. G. HALLDEN 1,868,705

S INGLE LINE REPEATER Filed June 6, 1930 :YQILZTI...

INVENTOR FREDERICK G. HALLDEN ATTOR Y Patented July 26, 1932 siren s'rAT EREEERICK G. I-IALLDEN, 0F JAMAICA, NEW YORK, ASSIGNOR TO INTERNATIONAL COMMUNICATIONS LABORATORIES, INC., 0F NEW YORK, N. Y., A CORPORATION OF NEW YORK SINGLE LINE REPEATER Application filed June '6, 1930. Serial No. 459,598.

the connecting lines by introducing repeaters 10 at intermediate points along the line.

Among the types of repeaters heretofore used for this purpose are those employing two or more relays in which both line circuit and local circuit windings are provided.

15 Most of these systems depend for their successful operation upon an extremely delicate adjustment of the proper balance between the forces respectively exerted upon the relays by the signalling impulses and by the 20 locally controlled currents and speed of transmission is often sacrificed in order to insure against operating the repeaters falsely.

Accordingly it is the primary object of this invention to provide repeating equipment in which the operation of the relays will be more positively controlled by the local currents and in which such control shall persist during moments when the relay armatures are in transit from one contact to another. A further object is to provide equivalent delays in the re-transmission of marking and spacing signals. It is obvious that the attainment of this latter object minimizes the distortion to which the retransmitted signals might otherwise be subjected. F urther objects will appear in the detailed description hereinafter given.

The invention may be more fully understood from the following description, together with the accompanying drawing in which:

Figure 1 represents diagrammatically one embodiment of the invention.

Fig. 2 represents also diagrammatically, a slightly modified arrangement.

Referring to Fig. 1, two stations are shown interconnected by lines 1 and 2 through the repeater se; P. The terminal stations comprise sounders or other receiving instruments 3, and grounded transmittings keys or their equivalent 1. f

Relays 5 and 6 in the repeater set have line circuit windings 7-8 and 9-10; also biasing coils 11-12 and 13-14. Two other relays 15 and 16 have operating coils 17-18 and biasing coils 19-20. Line 1 is grounded at station A when key 4 is closed. If desired, a battery maybe introduced between key 4 and ground.

This circuit includes station A, sounder 3 and winding 7 8 in the repeater relay 5 and connects through spacing contact and armature of relay 16 with the resistance 21 and grounded battery 22. Line 2 is grounded (optionally through a battery) at station B through key 4 and connects station B, sounder 3 with coil 9-10 in the repeater relay 6. This circuit also includes the spacing contact and armature of relay and thence it is connected through the resistance 23 with the grounded battery 2A. Various resistances and inductances are provided in connection with the other relay circuits as will be explained in describing the operation of the relays.

Referring to the modified arrangement shown in Fig. 2 it will be observed that the details at the terminal stations A-and B are exactly the same as shown in Fig. l. The I line circuits pass through relay windings 7-8 and 9-10 respectively as heretofore described. Non-polarized relay 32 (which is alternative to relay 15) is arranged with its coils 34-35 in series; and so likewise in regard to non-polarized relay 33 (which is alternative to relay 16). No biasing circuit is needed for these relays because their armatures are normally held against the marking contacts by springs 36. Other modifications will presently be set forth.

The operation of the repeater shown in Fig. 1 is as follows: If the operator at station A transmits signals over line 1 by opening and closing his key 4, then the current through coil 7-8 of relay 5 will be inter rupted. lVith the key 4 closed the direction of current is representedas from station A through line 1 to coil terminal 7, thence to coil terminal 8,' spacing contact PATENT iorrlce and armature 28 of relay 16, and through resistance 21 to negative battery The ampere turns in coil i"S may be adjusted to approximately twice the number of ampere turns set up in the opposite direction through the biasing coil 12-11. rrrmature 25 will then be held against the marking contact when key 1 is closed, and against the spacing contact when key t opened and in the latter case the biasing coil 1211 acts alone. Current is fed to coil terminal 12 through a resistance a from the grounded battery 31. After passing through the coil to terminal 11 this biasing circuit includes an inductance 87, the marking contact and armature 26 of relay 6, and finally a grounded resistance 38.

ll hen coil 1211 acts alone, the armature is thrown against its spacing contact, thus closing a circuit from grounded battery 39 through a resistance :0, coil 1T18 and thence to spacing contact and armature of relay This armature is grounded through the resistance ll. The ampere turns in coil 17-48 will be fixed at appro:-;imately twice the opposing ampere turns through the biasing coil 20-49, the latter being in a closed circuit which inc ides the battery -12 and resistance 13. He ice the shifting of armature 25 to the spacing contact of relay 5 results in shitting armature 27 to marking contact of relay 15, which opens the line circuit 2 and de-encrgizes the sounder 3 at station 13. The circuit through line 2 may be traced (assumin it to have been normally closed) from grounded key 1 at station 13. through the sounder 3, line to repeater se R, relay winding 9-10, spacing contact and armature 9 of relay and thence to resistance 23 and grounded battery 2 1. To hold this circuitopen while at the same time both lines 1 and 2 are kept under the control of the operator at station A, it is necessary that relays 6 and 16 should not at this time be actuated. This is accomplished as follows:

When line 2 is a closed circuit, the ampere turns developed in coil 9-10 oi relay 6 will exert a torce to hold armature 26 against the marking contact of relay 6. The opnosir i ampere turns ot the biasing coil l t-13 are normally adjusted to approxii .ately one-halt the force exerted by coil 910. But when relay operates to throw its armature against the spacing contact, the current in the biasing coil 13-111 is reversed. This is brought about by the proper choice of battery potentials and r sistances so that when armature is aga nst the mark n contact current will flow from battery 31 through resistance 0 and through the biasing coil 1-.t-123 of relay 6, nee through the inductance coil 1st tomzuking contactand armature 25 of relay 5, being grounded through a comparatively low resistance 11. .Vhen,

however, this circuit is opened by throwing armature 25 against the spacing contact, then current is fed from battery through the coinparatively high resistance 16 in the reverse direction through retard coil l1 and biasing coil l3-l-il-. thence thr ugh resistance (Z to ground. This change in the direction of current in the biasing coil 13-1s: takes place immediately upon separation of armature 25 from its marking contact and hence the enorgizing force in coil 131 l builds up to hold armature 26 against the marking contact before the current in coil 91O is dropped to Zero by being cut off at relay 15 spacing contact and armature 2 7 It will be understood, therefore, that when the transmission of signals originates at station A, relay 6 will not be operated and as long as this relay remains inactive, relay 16 will also remain inactive, thus keeping a closed path for line 1 through the snacing contact and armature 28 of relay 16, for obviously if the circuit were to be opened at this point then the operator at station A would lose his source of potential 22 and not be able to control the repeater by again closing his key 4.

When the key 1 at station A is again closed. the circuit through line 1 to ground cause. relay armature 25 to move to its marking: con tact. The circuit through coil 17-18 of re lay 15 is thus broken leaving the biasing coil LO-19 to act without opposition in throwing armature 2. against its si'iacing contact.

whercat the circuit in line 2 is again established. The biasing current through coil 1sl--13 is again reversed but not until arma true 25 has reached its marking contact and after further delay in passing th ough the inductance coil ll; whereas the current in coil 10 9 was more rapidly built up from the instant that armature 2T reached the spacing contact of relay 15; its excursion being practically simultaneous with that of armature on relay 5.

It is obvious from the symmetrical arrangement of the repeater relays and their connections. that transmission may be initiated with equal facility either at station A or :t tion B. If station E transmits. hen rcla 6 and 16 would operate precisely the same as has been described ith respect to relays 5 and 15 while the latter would then remain idle.

The operation of the modified arrangement shown in Fig. 2 will now be expla ned. The armature of relay 5 is normally held against its marking contact while current flows from grounded kcy -l at station A through line 1., coil 7 8, marking contact an d armature of non-polarized relay 3%, ance 21 and thence to grounded. battery lVhen the operator at station A opens his key 1, the coil 7-S becomes (lo-energized and as its ampere turns are adjusted to e;-;ert approximately twice. the force oppositely maintained in the biasing coil 12-11,

impressin upon the circuit at the point 51 a positive potential from battery 52 through the comparatively highresistance 53. Thus the relay 6 is caused toanticipate the loss of its holding current through coil 10-9 and at no time is there any tendency for its armature to leave the marking contact while transmission proceeds from station A.

The movement of armature 25 against the spacing contact of relay 5 causes a circuit to be completed through the coil 34l35 of the non-polarized relay 32, starting from grounded battery 39 and after passing through relay 32 to armature 25 is conducted to coil 1314 of relay 6 and thence through resistance (Z to ground. This current is in opposition to that proceeding frombattery 31 and is adjustedto overpower the latter in order to retain armature 26 against its marking contact while current ceases to flow in coil 910 of relay 6, this being the result of actuating relay 32 to open the circuit for line 2 at the parting of armature 29 from its marking contact.

The relay 32 is actuated against the tension of a spring 36 which tends to hold armature 29 against its marking contact. It will thus be seen that when key 4 is again closed at station A, and relay armature 25 of relay 5 moves away from its spacing contact, the breaking of the circuit through 0011 3i-35 will allow the spring 36 to restore armature 29 to marking contact, thereby reestablishing the closed circuit condition for line 2 from battery 24, the same as was described in reference to Fig. 1.

Just as there is a delay in transferring a spacing signal from line 1 to' line 2 due to the fact that armature 29 is not pulled away from its marking contact until arma ture 25 reaches its spacing contact, so also, a marking signal in line 1 is transferred to line 2 with such delay as is incidental to the travel time of armature 29 from spacing to marking contacts. The distortion of signals is therefore, practically negligible. As soon as armature 25 leaves its spacing contact, coil 3 i35 commences to de-energize. Hence the biasing spring 36 in relay 32 begins to actuate the armature 29 while armature 25 is in transit. The two armatures reach their marking contacts almost simultaneously and therefore the signalling impulse in line 2 builds up through coil 9-10 of relay 6 in opposition to the biasing current through coil 13-4 1 from battery 31. Since, however, this latter force is retarded by the inductance 50, there is no tendency for the current reversal in coil 13-14 to actuate the armature 26' and hence both relays 6 and 33 remain inactive during transmission from station A.

Transmission from station B will beeasily understood from the symmetrical arrangement ofthe repeater.

What is claimed is: v 1 1. Atelegraph repeater comprising two sets of relays, at least one relay of eachiset having a plural winding, a line connection with one of said plural windings in oneset, anotherline connection with a corresponding winding in the other set, a connection between the line connected winding of each set and a relay contact of the opposite set, a

connection between a relay contact of each set and .a winding of another relay in the same set, a biasing circuit in each set reversibly controlled by the actuation of a relay in the opposite set, and a local source of energy 9 for actuating the relays ofsaid repeater in response to line transmitted signals.

2. The invention set forth-in claim 1 in which the relays of one set are prevented from responding to the signals to which the other set responds.

3 The invention set forth in claim 1 in which the relays of one set are rendered inactive by a reversal of current flow in one of the windings anticipatory to a cessation of current fiow in another winding of the same relay.

4. The invention set forth in claim 1 in,

which the relays of one set are rendered inactive by delaying a reversal of current in one of the windings until after the current flow in another winding of the same relay has commenced to build up.

5. A- telegraph'repeater comprising a set of relays responsive to incoming signals from one loop circuit, another set of similar relays ies ilo

responsive to incoming signals from a second loop circuit,there being only one relay winding in each loop circuit and biasing windings in said relays, potential for energizing said windings and said loop circuits, means for re-transmitting the signals to which one setof relays is caused to respond to the loop circuit which includes the other set of relays and bias-reversal means to render said latter set of relays inactive during said re-transmitting of signals therethrough.

6. The invention set forth in claim 5 in which the bias-reversal means are respectively caused to anticipate or tolag behind the retransmitted signals according as the potential of'the latter is being reduced or built relay responsive to input signals, anotherline 7. A telegraph repeater comprisinga line '3 relay irresponsive to output signals conducted tlieretlirough, supplementary windings in said line relays, an auxiliary relay associated with each said line relay and operated thereby, means for reversing the current flow in the supplementary winding of the irresponsive line relay anticipatory to an interruption of currentflow representing an output signal caused by the actuation of one of said auxiliary relays.

8. A telegraph repeater comprising a line relay responsive to input signals, another line relay irresponsive to output signals conducted thercthrough, supplementary windings in said line relays, an auxiliary relay associated with each said line relay, means for causing one of said auxiliary relays to retransmit a signal anticipatory to a reversal of current flo in the supplementary winding of the irresponsive line relay.

9. A telegraph repeater comprising a line relay responsive to input signals, another line relay irresponsive to output signals conducted through a winding thereof, an auxiliary relay associated with each said line relay, means to actuate one of: said auxiliary relays from the responsive line relay to re-t-ransmit through the irresponsive line relay, and bias reversal means to lock the last said relay in advance of a re-transmitting circuit interruption and to unlock the same in arrears of a. re-transmitted impulse.

10. A telegraph repeater comprising a line relay responsive to input signals and irresponsive to output signals transmitted over a given line circuit, a retransmitting relay operable from said line relay, a second line relay and a second re-transmitting relay operable therefrom in response to input signals transmitted over a second line circuit and likewise irresponsive to output signals retransmitted over said second line circuit, current sources for said relays and for said line circuits, an armature marking and spacing contact device for each relay, main windings and auxiliary windings for each relay with biasing means whereby potential is duly applied from the current sources to the auxiliary windings of the line relay in opposition to the force of the input signals and in sustentation of the interrupted "force of the output signals.

1].. A telegraph repeater comprising a polar line relay for each of two loop circuits, and a re-transmitting relay associated with each line relay, there being only one relay winding included in each loop circuit.

12. A telegraph repeater comprising apair of polar line relays responsive to input signals and irresponsive to output signals, a retransmitting relay responsive to the operation of said responsive line relay for repeating signals through the other line relay, current reversing means controlled by the responsive line relay for preventing the operation of the other line relay and means controlled by said other line relay for preventing the operation of a retransmitting relay associated therewith.

13. A telegraph repeater comprising a pair of polar line relays responsive to input signals and irresponsive to output signals, signalling means for operating one oi said line relays, a retransmitting relay responsive to the operation of said operated line relay for repeating signals through the other line rclay, and means controlled by the responsive line relay for reversing the current in only one winding, said winding being the biasing winding of the other line relay.

14. A telegraph repeater comprising a pair of polar line relays responsive to input and irresponsive to output signals, a retransmitting relay responsive to the operation of one of said line relays for repeating signals through the other line relay, and means for reversing the current in only one winding, said winding being the biasing winding of the other line relay, when the operated line relay armature begins movement in one direction, and for again reversing the current in said winding when said armature ends its movement in the other direction.

15. A telegraph repeater comprising a line relay responsive to input signals, another line relay irresponsive to output signals conducted through a Winding thereof, an a-uxiliary relay controlled by each of said line relays, means for actuating one of said auxiliary relays from the responsive line relay to retransmit through the irresponsive line relay, and current reversing means for locking the irresponsive line relay in advance of a retransmitting circuit interruption and for unlocking said relay in arrears of a retransmitting circuit closure.

16. A telegraph repeater comprising a line relay responsive to input signals, another line relay irresponsive to output signals, an auxiliary relay associated with each of said line relays, means for actuating one of said auxiliary relays from the responsive line relay to retransmit through the irresponsive line relay, and current reversing means for looking the irresponsive line relay in advance of the operation of said auxiliary relay in one direction and for unlocking said relay in arrears of its operation in the other direction.

17. A telegraph repeater comprising two sets of relays in which the relays of one set are rendered inactive by delaying a reversal of current in a winding of a relay of the said set by means of an impedance in the circuit of the said winding until after the current in another winding of the same relay has commenced to build up.

18. A telegraph repeater comprising two sets of relays in which the relays of one set are rendered inactive by a reversal of current flow in a winding of but one relay of the said set anticipatory to a cessation of current flow in another winding of the same relay.

19. A telegraph repeater comprising two sets of relays in which the relays of one set are rendered inactive by reversing the current in a winding of but one relay of the said set and causing the current in said winding to build up more slowly than the current in another winding of the same relay.

In witness whereof, I hereunto subscribe my name this 4th day of June, 1930.

FREDERICK G. HALLDEN. 

